One type of network technology is known as Shortest Path Bridging (SPB). A set of standards for implementing Shortest Path Bridging is generally specified by the Institute of Electrical and Electronics Engineers (IEEE). Specifically, this standard is identified as IEEE 802.1aq. Network services, including SPB services are commonly provided using Ethernet technology. Ethernet has become a default Data Link Layer technology for data transport, that is, the default for Layer 2 (L2) of the Open Systems Interconnection (OSI) model. SPB can expand Ethernet technologies to other or larger networks. For example, a network that uses IEEE 802.1aq SPB can advertise both topology and logical network membership. SPB uses a link state protocol for such advertising.
In an SPB network, packets are encapsulated at an edge node in Mac-in-Mac 802.1ah and transported only to other members of the logical network. IEEE 802.1aq supports unicast and multicast, and all routing is on symmetric shortest paths. There exist other related technologies that follow the model of a provider network (transport network) that connects two or more customer networks (access networks), where the provider network is functionally distinct from the customer network, even if a single administrator runs both networks.
The SPB network typically includes a Backbone Edge Bridge (BEB) and a Backbone Core Bridge (BCB). BEBs (also known as provider network edge nodes) function as devices that enable transfer of packets to/from interfaces within the SPB network and to/from interfaces outside the SPB network.
Connectivity Fault Management (CFM) is an end-to-end per-service-instance Ethernet layer protocol that includes proactive connectivity monitoring, fault verification, and fault isolation. CFM uses maintenance points. A maintenance point is a demarcation point on an interface (port) that participates in CFM within a maintenance domain. Maintenance points on device ports act as filters that confine CFM frames within the bounds of a domain by dropping frames that do not belong to the correct level. Two classes of maintenance points exist, Maintenance Endpoints (MEPs) and Maintenance Intermediate points (MIPs).
MEPS exist at a per-maintenance domain (level) and service provider VLAN (S-VLAN). MEPs at an edge of a domain define the domain boundary. MEPs within the bounds of a maintenance domain confine CFM messages. When configured to do so, MEPs proactively transmit CFM continuity check messages (CCMs). At the request of an administrator, MEPs transmit traceroute and loopback messages.
MIPs exist at a per maintenance domain (level) and for all S-VLANs enabled or allowed on a port. MIPS are internal to a domain, not at the boundary. CFM frames received from MEPs and other MIPs are cataloged and forwarded. CFM frames at a lower level are stopped and dropped. All CFM frames at a higher level are forwarded.
Auto-attach is a proposed solution to allow devices which do not support Shortest Path Bridging (SPB) to attach to the SPBM network. To ensure the network is properly set-up and operating, the solution must ensure that there is appropriate debugging capabilities. Moreover, the network administrator must be able to confirm which devices have auto-attached to the network.